Appendix C RAID Controller Considerations
Embedded RAID Controller
Notes on Supported Embedded MegaRAID Levels
The following RAID levels are supported by the embedded MegaRAID controller.
•RAID 0—You can configure a RAID 0 virtual drive (VD) using one or more physical drives (PDs). This level supports up to eight VDs and PDs.
•RAID 1—A RAID 1 VD is configured from only two PDs. This level supports up to eight PDs (four RAID arrays) and eight VDs.
•RAID 5—You can configure a RAID 5 VD using three or more PDs. This level supports up to eight PDs and eight VDs.
•RAID 10—This is a spanned VD; that is, RAID 0 is implemented on two or more RAID 1 VDs. This level supports up to eight PDs (two to four RAID 1 volumes spanned) and one VD.
Note None of these RAID levels require drives of the same size. The smallest drive in the array determines the size of the VD.
Note An array can be divided into multiple VDs of the same RAID level, except when using RAID 10. Mixed arrays are not permitted. For example, you cannot configure a three-drive array into RAID 0 and RAID 5 VDs. Unlike RAID 0, 1, and 5, you cannot create multiple RAID 10 VDs from the same array. A single RAID 10 VD uses up the entire array.
Cisco UCS C22 Server Installation and Service Guide
